Ford plant drives green design

Planting the seeds of corporate ecological stewardship, Ford Motor Co. is using sustainable design as the driving force behind the $2 billion redevelopment of its historic Rouge Center manufacturing plant in Dearborn, Mich.

One of the world's largest and oldest industrial sites, part of the 1917 complex — once home to the Model A — is now a brownfield site, but not for long. The company has enlisted the services of William McDonough + Partners, Charlottesville, Va., a leading firm in the field of environmentally sensitive design, as a consultant on the project. Arcadis Giffels, Southfield, Mich., is the architect of record. Detroit-based Walbridge Aldinger is the general contractor.

The plan includes numerous pilots of advanced environmental concepts. According to Tim O'Brien, Ford director of environmental quality, ecological methods for energy usage, air quality and soil restoration will, in time, also be part of the modernized facility.

The sustainable centerpiece of the new assembly plant, which will replace the Dearborn Assembly Plant, is a 454,000-sq.-ft. "living roof" — the world's largest, according to Ford. The roof of the plant, which is under construction and expected to be completed in 2003, is being designed to provide a number of energy- and facilities-cost-saving benefits, according to William McDonough. The roof plays a major role in the project's integrated heating and cooling system, which McDonough says will make it one of the most efficient buildings anywhere in terms of BTUs used per person.

The 4-in.-deep sod roof will be covered with sedum, a succulent, drought-resistant groundcover, and other plants, selected by landscape architect Nelson Byrd, Charlottesville, Va. According to Rick Shriner, Arcadis Giffels' senior project manager, the added load placed on the structure by the green roof required a 25-pounds-per-square-inch incremental design capacity. "The roof has a cost premium associated with it," says Shriner, who adds that heavier steel, columns and trusses were needed. "Trying to build a first-cost business case is difficult. You have to look at the life of the project to justify the premiums."

The roof design is not yet final, but one system being considered consists of a sandwich of materials including filter fabric, a drainage layer, reinforced fabric, an underlayment, a roof membrane, fibrous sheathing and insulation.

Greenery acts as shield

"The greenery will protect the roof from wind in the winter — which is a huge part of its heating load — provide evaporative cooling, protect the roof from ultraviolet degradation and from thermal shock," says McDonough. "It should basically last forever.

"It's not some kind of green icing on a building, it's actually part of the habitat creation and stormwater management system," says McDonough. "The idea was to create a very cost-effective way to manage stormwater." Cost estimates for meeting clean-water regulations for the brownfield site over the next 10 years were $48 million, compared with $13 million for the McDonough plan.

From the roof, water will run off to porous asphalt paving, which percolates to a constructed biological botanical filter, then into swales filled with native trees, bushes and plants. They further percolate and filter the water as it flows toward the Rouge River. According to McDonough, the method yields water quality equivalent to that achieved by treatment in a large chemical treatment facility that would typically be designed to handle a major runoff event.